• 제목/요약/키워드: Se effect

검색결과 3,961건 처리시간 0.027초

홀로그래픽 격자 형성에 대한 칼코게나이드 박막의 열처리 효과 (Annealing Effect of the Chalcogenide Thin Film for Holographic Grating Formation)

  • 박정일;신경;이정태;이영종;정홍배
    • 한국전기전자재료학회논문지
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    • 제16권8호
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    • pp.736-739
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    • 2003
  • We prepared the chalcogenide As$\_$40/Ge$\_$10/Se$\_$15/S$\_$35/, Se$\_$75/Ge$\_$25/ thin film. Holographic grating was formed by the He-Ne laser( λ =633 nm). Annealing at 100$^{\circ}C$ and 200$^{\circ}C$ has been used to change the optical property of chalcogenide thin films for holographic grating formation. As the results, large variation of the optical property was generated at the As$\_$40/Ge$\_$10/Se$\_$15/S$\_$35/ chalcogenide film. Diffraction efficiency of the As$\_$40/Ge$\_$10/Se$\_$15/S$\_$35/ film has been enhanced about three times

Ag/a-$Se_{75}$$Ge_{25}$박막의 Ag Doping Mechaism 해석[I]

  • 김민수;이현용;정홍배;이영종
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 1994년도 춘계학술대회 논문집
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    • pp.113-115
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    • 1994
  • We considered the ion and photo-induced properties as a function of wavelength by exposing the light over the band gap of a-Ag/a-$Se_{75}$$Ge_{25}$ and the low-energy defocused $Ga^{+}$ ion beam on Ag/a-$Se_{75}$$Ge_{25}$ thin film. This film acts as a negative resist for photo or ion beam lithography. We observed that the absorbance coefficient decreased with increasing the photo-exposing time and exposing the ion beam. The bandgap shifts toward longer wavelength called a "darkening effect" are observed in the films exposed to both photons and ions. We suggest that a primary step in the Ag layer and a secondary step is in a-$Se_{75}$$Ge_{25}$ film layer.

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광전류 측정으로부터 얻어진 $CdGa_2Se_4$ 에피레이어의 결정장 갈라짐에 대한 에너지 (Crystal field splitting energy for $CdGa_2Se_4$ epilayers obtained by photocurrent measurement)

  • 홍광준
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2009년도 하계학술대회 논문집
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    • pp.144-145
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    • 2009
  • Single crystal $CdGa_2Se_4$ layers were grown on a thoroughly etched semi-insulating GaAs(100) substrate at $420^{\circ}C$ with the hot wall epitaxy (HWE) system by evaporating the poly crystal source of $CdGa_2Se_4$ at $630\;^{\circ}C$. The crystalline structure of the single crystal thin films was investigated by the photoluminescence and double crystal X-ray diffraction (DCXD). The carrier density and mobility of single crystal $CdGa_2Se_4$ thin films measured with Hall effect by van der Pauw method are $8.27\;\times\;10^{17}\;cm^{-3}$, $345\;cm^2/V{\cdot}s$ at 293 K, respectively. The photocurrent and the absorption spectra of $CdGa_2Se_4$/SI(Semi-Insulated) GaAs(100) are measured ranging from 293 K to 10K. The temperature dependence of the energy band gap of the $CdGa_2Se_4$ obtained from the absorption spectra was well described by the Varshni's relation, $E_g$(T) = 2.6400 eV - ($7.721\;{\times}\;10^{-4}\;eV/K)T^2$/(T + 399 K). Using the photocurrent spectra and the Hopfield quasi cubic model, the crystal field energy(${\Delta}cr$) and the spin-orbit splitting energy(${\Delta}so$) for the valence band of the $CdGa_2Se_4$ have been estimated to be 106.5 meV and 418.9 meV at 10 K, respectively. The three photocurrent peaks observed at 10 K are ascribed to the $A_1$-, $B_1$-, and $C_{11}$-exciton peaks.

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흑연로원자흡수분광법에 의한 쌀분말시료중의 비소, 납, 셀레늄의 정량 (Determination of Arsenic, Lead and Selenium in Rice Flour by Graphite Furnace Atomic Absorption Spectrometry)

  • 조경행;서정기
    • 분석과학
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    • 제12권2호
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    • pp.130-135
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    • 1999
  • 쌀분말시료중에 미량으로 존재하는 비소(As), 납(Pb), 셀레늄(Se)등을 분석하기 위하여 매질변형방법에 의한 흑연로원자흡수분광법을 이용하였다. 흑연로내에서 측정원소의 열안정성과 간섭매질의 휘발성을 증가시키기 위해 매질변형재로서 팔라듐과 질산마그네슘 혼합물을 사용하였다. 몇가지 금속원소(As, Cd, Cu, Pb, Se, Zn)에 대해 팔라듐과 질산마그네슘 혼합물에 의한 매질변형효과를 검토한 결과 As, Pb, Se에 대해 뚜렷한 회화 및 원자화 온도의 증가와 흡수도 상승효과를 확인 하였다. 마이크로파 산가압분해법에 의해 쌀분말시료를 분해하고 표준물첨가법에 의해 As, Pb, Se을 분석하였다. 바탕선 보정에는 Zeeman effect를 이용하였으며 특성농도는 건조시료기준 As 26 ng/g, Pb 18 ng/g, Se 24 ng/g이었다.

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Heterophil Phagocytic Activity Stimulated by Lactobacillus salivarius L61 and L55 Supplementation in Broilers with Salmonella Infection

  • Sornplang, Pairat;Leelavatcharamas, Vichai;Soikum, Chaiyaporn
    • Asian-Australasian Journal of Animal Sciences
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    • 제28권11호
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    • pp.1657-1661
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    • 2015
  • Newborn chicks are susceptible to Salmonella enterica serovar Enteritidis (SE). The objective of this study was to evaluate the effect of Lactobacillus probiotic isolated from chicken feces on heterophil phagocytosis in broiler chicks. A total of 150 newborn broiler chicks were divided into 5 groups (30 chicks per group) as follows: group 1 (normal control), given feed and water only, group 2 (positive control) given feed, water and SE infection, group 3 (L61 treated) given feed, water, SE infection followed by Lactobacillus salivarius L61 treatment, group 4 (L55 treated) given feed, water, SE infection followed by L. salivarius L55 treatment, and group 5 given feed, water, SE infection followed by L. salivarius L61 + L55 combination treatment. After SE infection, L. salivarius treatment lasted for 7 days. The results showed that L. salivarius L61 and L. salivarius L55 treatment, either alone or combination of both, increased the survival rate after SE infection, and upregulated heterophil phagocytosis and phagocytic index (PI). Conversely, chick groups treated with Lactobacillus showed lower SE recovery rate from cecal tonsils than that of the positive control group. The PI values of the chicken group with SE infection, followed by the combination of L. salivarius L61 and L. salivarius L55 were the highest as compared to either positive control or normal control group. Two Lactobacillus strains supplementation group showed significantly (p<0.05) higher PI value at 48 h than 24 h after treatment.

Cyclic Voltammetry를 이용한 CuInSe2 박막의 전기화학적 전착 연구 (Cyclic Voltammetry Study on Electrodeposition of CuInSe2 Thin Films)

  • 홍순현;이현주;김양도
    • 한국재료학회지
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    • 제23권11호
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    • pp.638-642
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    • 2013
  • Chalcopyrite $CuInSe_2$(CIS) is considered to be an effective light-absorbing material for thin film photovoltaic solar cells. CIS thin films have been electrodeposited onto Mo coated and ITO glass substrates in potentiostatic mode at room temperature. The deposition mechanism of CIS thin films has been studied using the cyclic voltammetry (CV) technique. A cyclic voltammetric study was performed in unitary Cu, In, and Se systems, binary Cu-Se and In-Se systems, and a ternary Cu-In-Se system. The reduction peaks of the ITO substrate were examined in separate $Cu^{2+}$, $In^{3+}$, and $Se^{4+}$ solutions. Electrodeposition experiments were conducted with varying deposition potentials and electrolyte bath conditions. The morphological and compositional properties of the CIS thin films were examined by field emission scanning electron microscopy (FE-SEM) and energy dispersive spectroscopy (EDS). The surface morphology of as-deposited CIS films exhibits spherical and large-sized clusters. The deposition potential has a significant effect on the film morphology and/or grain size, such that the structure tended to grow according to the increase of the deposition potential. A CIS layer deposited at -0.6 V nearly approached the stoichiometric ratio of $CuIn_{0.8}Se_{1.8}$. The growth potential plays an important role in controlling the stoichiometry of CIS films.

온라인 학습에서 콘텐츠의 제시유형과 제시수준, 메타인지가 학습에 미치는 효과 (The effect of contents presentation types, levels and metacognition on concept map in online learning)

  • 이성주;전희정;나재희
    • 컴퓨터교육학회논문지
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    • 제16권6호
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    • pp.71-81
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    • 2013
  • 본 연구는 온라인 학습에서 콘텐츠의 제시유형과 제시수준, 그리고 학습자의 메타인지가 학습에 미치는 영향을 살펴보고자 실시되었다. 이를 위해 온라인 학습 콘텐츠의 제시유형과 제시수준, 그리고 학습자의 메타인지에 따른 개념도 형성과 학습 과정을 살펴보았다. 온라인 학습 콘텐츠의 제시유형은 의미중심형과 맥락중심형으로, 제시수준은 기본형과 결핍형으로 구분하여 제공하였고, 학습자의 메타인지는 검사결과에 따라 상하 두 집단으로 구분하였다. 연구결과는 콘텐츠의 제시유형에서 의미중심형(M=45.00, SE=1.97)이 맥락중심형(M=34.71, SE=1.98)보다 더 높은 개념도 형성을 보였다. 콘텐츠의 제시수준별 집단간(F=.002, p>.05), 메타인지 상하 집단간에는 의의 있는 차이가 없었다. 그러나 제시수준과 메타인지 사이에 상호작용(F=6.225, p<.05) 효과가 있어 메타인지 상집단은 결핍형에서, 하집단은 기본형에서 보다 높은 개념도 형성을 보였다. 또한 온라인 학습 과정 분석을 통해 학습자의 메타인지가 콘텐츠의 결점과 결핍을 보완하여 학습을 실행하게 하는 중요요인임을 확인할 수 있었다.

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The Effect of Spent Medium Recycle on Cell Proliferation, Metabolism and Baculovirus Production by the Lepidopteran Se301 Cell Line Infected at Very Low MOI

  • Beas-Catena, Alba;Sanchez-Miron, Asterio;Garcia-Camacho, Francisco;Contreras-Gomez, Antonio;Molina-Grima, Emilio
    • Journal of Microbiology and Biotechnology
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    • 제23권12호
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    • pp.1747-1756
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    • 2013
  • The aim of this paper was to study the effect of spent medium recycle on Spodoptera exigua Se301 cell line proliferation, metabolism, and baculovirus production when grown in batch suspension cultures in Ex-Cell 420 serum-free medium. The results showed that the recycle of 20% of spent medium from a culture in mid-exponential growth phase improved growth relative to a control culture grown in fresh medium. Although both glucose and glutamine were still present at the end of the growth phase, glutamate was always completely exhausted. The pattern of the specific glucose and lactate consumption and production rates, as well as the specific glutamine and glutamate consumption rates, suggests a metabolic shift at spent medium recycle values of over 60%, with a decrease in the efficiency of glucose utilization and an increase in glutamate consumption to fuel energy metabolism. Baculovirus infection provoked a change in the metabolic pattern of Se301 cells, although a beneficial effect of spent medium recycle was also observed. Both growth rate and maximum viable cell density decreased relative to uninfected cultures. The efficiency of glucose utilization was dramatically reduced in those cultures containing the lowest percentages of spent medium, whereas glutamine and glutamate consumption was modulated, thereby suggesting that infected cells were devoted to virus replication, retaining their ability to incorporate the nutrients required to support viral replication. Recycle of 20% of spent medium increased baculovirus production by around 90%, thus showing the link between cell growth and baculovirus production.

오적산(五積散)이 Estradiol Valerate로 유발된 다낭성 난소 모델에서 난포의 성숙 및 NGF발현에 미치는 영향 (Effects of Ojeok-san on the Maturation of Follicles and NGF Expression in Rats with Estradiol Valerate-induced Polycystic Ovaries)

  • 김종대;서일복;이동녕;김형준
    • 대한한방부인과학회지
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    • 제24권1호
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    • pp.27-41
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    • 2011
  • Objectives: This study was designed to investigate the effect of Ojeok-san(OJS) on the estradiol valerate(EV)-induced polycystic ovaries(PCO) in rats. Methods: PCO was induced by single intramuscular injection with estradiol valerate(EV)(4mg) in female rats. Normal group(n=8) were injected with sesame oil and orally administrated distilled water for sixty days. PCO control group (n=8) were injected with EV and orally administrated distilled water for sixty days. OJS treated group(n=8) were injected with EV and orally administrated OJS for sixty days. Then, we measured weights of body, ovaries, adrenal glands and uterus of rats. The histomorphometrical changes of ovaries were also evaluated. And we observed the NGF and CRF expression by immunohistochemistry. Results: The results were as follows - The weights(mg) of ovaries in OJS treated group($57.4{\pm}9.4$) were significantly increased(p < 0.05) compared with PCO control group($42.3{\pm}8.5$). - The numbers of mature follicles in OJS treated group($9.3{\pm}2.5$) were significantly increased(p < 0.05) compared with PCO control group($6.1{\pm}2.1$). - The expressions of NGF-immunoreactive cells in the ovarian granulosa cells in OJS treated group were weaker than PCO control group. Conclusion: From the these results, we concluded that Ojeok-san(OJS) has inhibitory effect on the development of EV-induced polycystic ovary. And it's effect maybe related with decreased NGF activities in the ovary.

Methionine과 Selenium 수준이 흰쥐의 알코올대사 효소계에 미치는 영향 (Effect of Methionine and Selenium Levels on Alcohol Metabolic Enzyme System in Rats)

  • 김명주;박은미;이미경;조수열
    • 한국식품영양과학회지
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    • 제26권2호
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    • pp.319-326
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    • 1997
  • Met과 Se의 공급수준이 흰쥐의 알코올대사 효소계에 미치는 영향을 관찰하고자, Sprague-Dawley종의 웅성 흰쥐에게 Se 무첨가 및 정상공급식이 (0, 0.45mg/kg diet)에 Met(0, 3, 9g/kg diet)을 투여한 후 5주와 10주간 사육하여 간조직중의 알코올 대사효소와 항산화 방어 효소계 활성도를 관찰하였다. 알코올은 aldehyde dehydrogenase와 microsomal ethanol oxidizing system 활성도를 유의적으로 증가시켰으며, Met과 Se의 동시 결핍시 현저하게 감소하였고 Met과 Se의 동시 공급군의 경우 알코올 투여기간이 길수록 그 활성이 유의적으로 증가하였다. Aldehyde dehydrogenase 활성도는 알코올 투여로 감소하였으며 Met과 Se 동시 결핍군에서는 현저한 감소를 나타내었고, 사육기간이 길수록 그 활성이 유의적으로 감소되었다. Cytochrome P-450과 xanthine oxidase 활성도는 알코올 투여 시 유의적으로 증가되었는데 Se 결핍시 Met 결핍군과 과량공급군에서 그 증가가 현저하였으며, 5주 실험군에 비해 10주 실험군에서 유의적인 증가를 나타내었다. Superoxide dismutase, catalase 및 glutathione S-transferase 활성도는 알코올 투여시 증가되었으며, superoxide dismutase와 catalase 활성도는 알코올 투여기간이 길수록 유의적인 증가를 나타내었다. 알코올 투여시 glutathione peroxidas 활성도는 감소되었으며, Met 수준이 높을수록 증가하는 경향이었고, Met과 Se 동시 결핍시 현저하게 감소하였다. 이상의 결과에서 식이성 Met과 Se은 동물의 성장 및 정상적 대사유지에 필수적인 영양소로서 알코올 투여 시 Met과 Se 첨가에 따라 알코올대사 효소활성도와 항산화 방어효소 활성도의 변화를 유도할 수 있었다. 또한 식이 kg당 3g의 Met과 0.45mg의 Se 동시 공급시 원활한 알코올대사를 유도하여 알코올성 간손상을 가장 효율적으로 경감시킬 수 있는 것으로 나타났다.

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